Electron keyboard layout
                                       ========================

      +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
      |     |  !  |  "  |  #  |  $  |  %  |  &  |  '  |  (  |  )  |  @  |  =  | ^ ~ | | \ |     |
      | ESC |  1  |  2  |  3  |  4  |  5  |  6  |  7  |  8  |  9  |  0  |  -  | LEFT|RIGHT|BREAK|
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
         |CAPS |  Q  |  W  |  E  |  R  |  T  |  Y  |  U  |  I  |  O  |  P  | £ { | _ } | [ ] |
      o  | FUNC|  q  |  w  |  e  |  r  |  t  |  y  |  u  |  i  |  o  |  p  |  UP | DOWN| COPY|
         ++----++----++----++----++----++----++----++----++----++----++----++----++----+---+-+
          |     |  A  |  S  |  D  |  F  |  G  |  H  |  J  |  K  |  L  |  +  |  *  |        |
          | CTRL|  a  |  s  |  d  |  f  |  g  |  h  |  j  |  k  |  l  |  ;  |  :  | RETURN |
          +-----+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-----+--+--+
          |        |  Z  |  X  |  C  |  V  |  B  |  N  |  M  |  <  |  >  |  ?  |        |     |
          |  SHIFT |  z  |  x  |  c  |  v  |  b  |  n  |  m  |  ,  |  .  |  /  | SHIFT  | DEL |
          +--------+-----+--+--+-----+-----+-----+-----+-----+-----+-----+--+--+--------+-----+
                            |                                               |
                            |                                               |
                            +-----------------------------------------------+


                                       Electron keyboard keycodes
                                       ==========================

      +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
FUNC  | &1B | &81 | &82 | &83 | &84 | &85 | &86 | &87 | &88 | &89 | &80 | &AD | &8C | &8D |     |
CTRL  | &1B |  1  |  2  |  3  |  4  |  5  |  6  |  7  |  8  |  9  | &00 | &1D |  ~  |  \  |     |
SHIFT | &1B |  !  |  "  |  #  |  $  |  %  |  &  |  '  |  (  |  )  |  @  |  =  |  ^  |  |  |BREAK|
      | &1B |  1  |  2  |  3  |  4  |  5  |  6  |  7  |  8  |  9  |  0  |  -  | &8C | &8D |     |
      | ESC |     |     |     |     |     |     |     |     |     |     |     | LEFT|RIGHT|     |
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
FUNC     |     | &A0 | &A6 | &94 | &A1 | &A3 | &A8 | &A4 | &98 | &9E | &9F | &8F | &8E | &8B |
CTRL     |     | &11 | &17 | &05 | &12 | &14 | &19 | &15 | &09 | &0F | &10 |  {  |  }  |  ]  |
SHIFT    |CAPS |  Q  |  W  |  E  |  R  |  T  |  Y  |  U  |  I  |  O  |  P  |  £  |  _  |  [  |
      o  | FUNC|  q  |  w  |  e  |  r  |  t  |  y  |  u  |  i  |  o  |  p  | &8F | &8E | &8B |
         |     |     |     |     |     |     |     |     |     |     |     |  UP | DOWN| COPY|
         ++----++----++----++----++----++----++----++----++----++----++----++----++----+---+-+
FUNC      |     | &90 | &A2 | &93 | &95 | &96 | &97 | &99 | &9A | &9B | &AB | &AA |  &0D   |
CTRL      |     | &01 | &13 | &04 | &06 | &07 | &08 | &0A | &0B | &0C | &3B | &3A |  &0D   |
SHIFT     | CTRL|  A  |  S  |  D  |  F  |  G  |  H  |  J  |  K  |  L  |  +  |  *  |  &0D   |
          |     |  a  |  s  |  d  |  f  |  g  |  h  |  j  |  k  |  l  |  ;  |  :  |  &0D   |
          |     |     |     |     |     |     |     |     |     |     |     |     | RETURN |
          +-----+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-----+--+--+
FUNC      |        | &A9 | &A7 | &92 | &A5 | &91 | &9D | &9C | &AC | &AE | &AF |        | &7F |
CTRL      |        | &1A | &18 | &03 | &16 | &02 | &0E | &0D | &1C | &1E | &1F |        | &7F |
SHIFT     |  SHIFT |  Z  |  X  |  C  |  V  |  B  |  N  |  M  |  <  |  >  |  ?  | SHIFT  | &7F |
          |        |  z  |  x  |  c  |  v  |  b  |  n  |  m  |  ,  |  .  |  /  |        | &7F |
          |        |     |     |     |     |     |     |     |     |     |     |        | DEL |
          +--------+-----+--+--+-----+-----+-----+-----+-----+-----+-----+--+--+--------+-----+
                            |                      &20                      |
                            |                     SPACE                     |
                            +-----------------------------------------------+


                                        Electron Keymapping
                                        ===================
                                   Electron Keymapping
                                   ===================

+==+====+====+====+====+====+====+====+====+====+====+=====+=====+=====+=====+=====+=====+
|  | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | x8 | x9 | xA  | xB  | xC  | xD  | xE  | xF  |
+==+====+====+====+====+====+====+====+====+====+====+=====+=====+=====+=====+=====+=====+
|0x| c0 | cA | cB | cC | cD | cE | cF | cG | cH | cI | cJ  | cK  | cL  | cM  | cN  | cO  |
|  |    |    |    |    |    |    |    |    |    |    |     |     |     |Retrn|     |     |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|1x| cP | cQ | cR | cS | cT | cU | cV | cW | cX | cY | cZ  | Esc | c,  | c-  | c.  | c/  |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|7x|    |    |    |    |    |    |    |    |    |    |     |     |     |     |     | Del |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|8x| f0 | f1 | f2 | f3 | f4 | f5 | f6 | f7 | f8 | f9 |     | Copy| <-  | ->  | Dn  | Up  |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|9x| fA | fB | fC | fD | fE | fF | fG | fH | fI | fJ | fK  | fL  | fM  | fN  | fO  | fP  |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|Ax| fQ | fR | fS | fT | fU | fV | fW | fX | fY | fZ | f:  | f;  | f,  | f-  | f.  | f/  |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|Bx|    |    |    |    |    |    |    |    |    |    |     |     |     |     |     | Del |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+
|Cx|    |    |    |    |    |    |    |    |    |    |Break|     |     |     |     |     |
+--+----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+

Top-bit-set keypresses are translated with *FX221-*FX228. Setting characters &9x and &Ax
to &01 programs them to be language firm keys rather than *KEY soft keys. There is no TAB
key on the Electron keyboard. After-market additions generate Ctrl-H.

Because of the restricted Electron keyboard there is no such thing as modified function or
editing keys. For instance, SHIFT+cursors gives £ _ ^ | and not Shift+fkey.

Modified Electron cursor keys can be translated to standard keycodes with the following code:

To generate editing key characters &87-&8B:
  * in program startup use:
    *FX4,1
  * when reading keypresses use:
    K%=GET
    IF INKEY-256=1:A%=INSTR("[^|_`]~\}{",CHR$K%)-1:IF A%>-1:K%=&87+A%MOD5

For standard keycodes:
  * in program startup use:
    *FX4,2
    *FX225,128
  * when reading keypresses use:
    K%=GET
    IF INKEY-256=1:A%=INSTR("[^|_£]~\}{",CHR$K%)-1:IF A%>-1:K%=(A%DIV5)*16+&9B+(A%MOD5)